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, M. W. DEWEY METHOD OF ELECTRIC WELDING 0R METAL WORKING.

No. 430,838. Patented June 24, 1890.

UNITED STATES PATENT OFFICE.

MARK \V. DEWEY, OF SYRACUSE, NElV YORK, ASSIGNOR TO THE DEWEY CORPORATION, OF SAME PLACE.

METHOD OF ELECTRIC WELDING OR METAL-WORKING.

SPECIFICATION forming part of Letters Patent No. 430,838, dated June 24, 1890.

Application filed October 14, 1889. Serial No. 326,937. (No model.) i

To all whmn it may concern.-

Be it known that I, MARK W. DEWEY, of Syracuse, in the county'of Onondaga, in the State of. New York, have invented new and useful Improvements in Methods of Electrically Heating Bars, &c., forNVelding and Vorking Purposes, of which the following, taken in connection with the accompanying drawings, is a full, clear, and exact description.

My invention relates to the application of heat to the part or parts of metal or other material to be welded, worked, or treated; and it consists, essentially, in exposing or subjecting the said part or parts to be operated upon to the heat of a continuous electrically-heated conductor in proximity thereto, thereby heating the said part or parts to the required welding, working, or treating temperature.

My invention consists, further, in enveloping the part or parts to be heated and operated upon by the heating-conductor; also, in preventing radiation of heat from the said heating-conductor in directions not toward said part or parts; audit consists, still further, in conducting the heat from the said conduetor to the said part or parts through a non-electric conducting or high-resistance electric conducting -medium.

My invention may be utilized for effecting all manner of welding, soldering, brazing, working, or treating operations of metals, and also for operations upon partial and nonconducting bars.

Some of the advantages of my method of heating the work for the above operations are as follows: The heat is applied directly to the exterior of the bar or blank at the point to be welded or treated, and thereby heating the same to the required temperature. By thus first heating the exterior of the bar or blank I insure a perfect weld.

It is a well-known fact that bars or blanks when subjected to torsional or lateral strain,

the greatest strain is exerted near the sur face of the bar or blank, especially when subjected to fiexurc, in which case the central portion constitutes the neutral axis at which no strain is exerted, while a compressive strain is exerted at one side of the neutral axis and a tensile strain at the opposite side of said axis, and said strains gradually increase to the exterior of the bar or blank. In View of this fact it is obvious that it is more essential that the exterior of a bar be united thoroughly than the interior thereoflcspecially when the bar or blank is designed to resist the aforesaid strain. Therefore this method is superior to that where the heatingcurrent is passed through the bar itself, as

the interior of the bar in the latter case is heated more than the exterior on account of the radiation of heat therefrom, and thus, while a good welding or union may be effected of the interior of the bar, the union of the exterior is liable to be incomplete, or a burning of the interior may be caused, While the exterior is properly heated and united.

Further, by my invention bars or blanks of different sizes and conductivities can be heated without varying the volume of the current, and transformation of the current is unnecessary in many cases, or at least not to the great extent usually required, on account of the high resistance of the heating-conductor that may be employed for my method. In the accompanying drawings, Figures 1 and 2 are respectively sectional and side elevations of an apparatus adapted for accomplishing my method of treating metals. Figs. 3 and 4 are respectively sectional and side elevations of another form of the heating part of said apparatus. Fig. 5 is a sectional view, similar to Fig. 3 of another form of the heating apparatus. Fig. 6 is a side elevation of a more simplified form of the apparatus shown in Fig. 2. Figs. 7 and 8 are cross-sectional views of modified forms of apparatus, and Fig. 9 shows another form of apparatus adapted for carrying out the object of my invention.

Referring specifically to the drawings, A in Figs. 1 and 2 represents the bar or bars to be heated, worked, or welded, supported upon twosupports B and B and secured thereto by clamps b and I). .SupportB is stationary,

and B is movable toward and from the other support, so that by the moving of the support B by means of thescrew D the bar or bars held by said supports can be subjected either to compression endwise or to tension or drawing out lengthwise, as may be desired.

too

C is the heating-conductor, located between the aforesaid supports at the point of the bar or blank A to be operated upon, and is supported by two supports 0 and c, mounted upon the base-plate a of the apparatus, but insulated therefrom and from each other by insulation (1. The heating or heat-radiating conductor 0 and its supports may be moved to any position or location between the supports 13 and B to effect the heating of any desired point along the bar, and there fastened by means of the clamp c.

f and f are the terminals of the heatingconductor, which may be of low resistance, and are connected to the supports 0 and c.

The heating-current to be employed may be generated by any suitable meansas, for instance, that described in my prior patents in metal-working, No. 02,llo',dated April 30, 1889, and No. @8575, dated August 13, 1889.

The supports 0 and 0 form the terminals of the said heating-conductor U, which preferably envelops or surrounds the bar A, and is in two parts, so that the same can be readily applied to the bar to be heated and removed from the said bar after the temperature of the work is raised to the required extent. The upper part of the conductor 0 is hinged to the lower part, in this case by the hinge E at the ends of the arms 5 and g, extending from the conductor C rearward, and by means of a handle 71, extending from the said upper part toward the front of the apparatus, said part of the conductor can be easily lifted from the lower part until arrested by stops 1' 1" on the hinged ends of the arms 9 g, which stops are in such positions as to sustain the lifted part in a rearwardlyinclined position and at rest. The said parts of C can be held separated more or less to allow radiation or the escape of heat therefioin to control the temperature of the bar A or to permit the latter to be observed during the heating of the same or operation after it is heated by means of the stop-screw (Extending through the arm and resting with its lower end upon the top of the arm 7. The conductor is continuous or unbroken, and maybe heated,of eourse,to any desirable extent, even to incandeseence, and to prevent waste of heat said conductor may be enveloped or inclosed. by a covering or envelope h, of some refractory or non-heat-conducting material, such as fii'U' Jl'iC'ii or asbestus, as Shown in Figs. 3 and l.

In Figs. and a the parts of the conductor 0 are not hinged together; but the upper part is intended to be lifted bodily from the lower part by means of the handles 7; ll.

In some cases, when a very great heat is not required, this apparatus may be used without. the upper part of the conductor C. Fig. 7 shows a sectional view of a modification of a similar apparatus where neither the heatingconduetor nor the non-heat-coilductiug material completely surrounds the bar A.

Fig. 5 illustrates a sectional view similar to Fig. 3; but the conductor 0 is lined with a substance G that maybe raised to incandescence and conduct the heat from the conductor C to the bar A, with which it is in contact. This substance G, forming the lining of the conductor, maybe of compressed baked clay or carbon or other suitable substance. It composed of carbon, oxidation of the metal when heated will be prevented to a great extent. \Vhile linings formed of the substances referred to are imperfect conductors of heat, they are much better than the air and indestructible or fire-proof to a great extent, and also on account of their high-resistance prevent the low-tension electric current employed to sl10rtcircuit through them and bar A. In some cases this lining G may not come in contact with the bar A, but simply be brought in close proximity thereto.

Fig. 8 is a modification of Fig. 5, and represents the conductor 0 formed into a box or trough and the lining G formed of: some granulated materialas carbon, coal, sand, or other substance-in which the bar A is buried.

In the simple form of the apparatus illustrated in Fig. (5 theheat-radiating conductor-(1 is simply a bar or wire connected at each end to its supports a and e and running along parallel with and in close proximity to the bar or blank A. The heating-conductor C in Fig. 0 is of the form of a coil, and the bar A is within the same, but not in contact therewith.

It will be obvious that the apparatus may be greatly modilied without departing from the spirit of my invention, as its scope is not confined to the specific form or arrangements of apparatus shown and described herein.

I do not claim, broadly, the method of uniting metals or other objects by the application of heat, consisting in passing a heating electric current through a conductor in juxtaposition to the work, inasmuch as said method has been resorted to in uniting metals by solder or cement.

The apparatus herein shown is not specifically claimed, as it forms the subject-matter of another applieatiim, Serial No. 341L165, iilcd by me April 0, 1590, as a division of this application.

l'laving described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. The herein-descril)ed method of electric welding or metalavorking, consisting in placing the bar or blank in proximity to an electric heat-rzuliating conductor and then pass ing an electric heating-current through said heatradiating conductor, partly or wholly surrounding the conductor by a refractory or non-heat-eonducting material, thereby raising the temperature of the work to the required extent, and then welding, working, or treating the work as desired.

2. The herein-described method of: electric welding or metal-working, consisting in placing the bar or blank in proximity to an electrio heat-radiating conductor and then passing an electric heating-current through said heat-radiating conductor, partly or wholly surrounding the conductor by a refractory or non-heat-conductin g material, conducting the heat from the conductor to the work through a non-electric conducting or a high-resistance conducting substance, thereby raising the temperature of the work to the required degree, and then welding, working, or treating the said work as desired.

The herein-described method of electric welding or metal-workin g, consisting in enveloping the work to be welded or otherwise operated upon or treated in a heat-radiating electric conductor, thereby heating said work to the requisite temperature, and then subjectin g said work to the desired operation or treatment.

4. The herein-described method of electric welding or metal-working, consisting in enveloping the work to be welded or otherwise operated upon or treated in a heat-radiating electric conductor, partly or wholly surrounding the conductor by a refractory or non-heatconducting material, thereby heating the latter to the requisite temperature, and then performing the desired operation or treatment upon the work.

5. The herein-described method of electric welding or metal-working, consisting in enveloping the work to be welded or otherwise operated upon or treated in an electric conductor, passing an electric hcatingcurrent through the latter, partly or wholly surrounding the conductor by a refractory or non-heatconducting material, conducting the heat from the conductor to the work through a non-electric conducting or a high-resistance conducting substance, thereby raising the temperature of the work to the required degree, andthen welding, working, or treating the said work as desired.

6. The herein-described method of electric welding or metal-working, which consists in suitably supporting the work upon two supports, locating a heat-radiating electric conductor between the supports in proximity to and enveloping said work at the point to be heated, surrounding both the radiating-conductor and the work with a non-heat-conducting envelope, connecting the terminals of a low-resistance heating-current conductor with the said heat-radiating conductor, and thereby heating the work to the requisite welding, working, or treating temperature, and then treating the said work as desired.

7. The herein-described method of electric welding or metal-working, consisting in subjecting or exposing the work to the heat of a heat-radiating electric conductor,controlling the heating of the work by Varying the confinement or retainment of the heat, and thereby raising the temperature of the work to the required extent, as and for the purpose described.

8. The herein-described method of welding or metal-working, consisting in enveloping the work to be operated upon or treated in an electric conductor, passing an electric heating-current through the latter, thereby raising the temperature of the work to the required extent, then removing said conductor and working or treating the work as desired.

9. The herein'described method of electric welding or metal-working, consisting in subjecting or exposing the work at apoint to be heated to the heat of an incandescent highresistance body raised to incandescence by the heat of a continuous incandescent electrio conductor in contact with said body, thereby heating the work to the required temperature, as and for the purpose described.

In testimony whereof I have hereunto signed my name this 11th day of October, 1889.

MARK \V. DEWEY. 

